Machine for forming metal stock for hot forging

ABSTRACT

A machine for deforming the end of a piece of metal for handling it for insertion into a forging press or the like to form the finished article. The machine receives, holds and deforms a piece of metal which has been heated to a plastic condition, and has stop means for holding the piece against axial shifting in one direction while its squeezing jaws deform the end of the piece into a holding portion. The swingable jaws of the machine are of a shape (1) that precludes axial shifting of the piece in the other direction and (2) that forms the holding portion into a flattened and axially elongated shape having tool engaging projections.

United States Patent [191 Andresen [541 MACHINE FOR FORMING METAL STOCK FOR HOT FORGING Related U.S. Application Data [62] Division of Ser. No. 148,092, May 28, 1972, Pat. No.

FOREIGN PATENTS OR APPLICATIONS 48,425 9/1964 Poland 72/412 Primary Examiner-Charles W. Lanham Assistant Examiner-Gene P. Crosby Attorney-James E. Nilles [5 7] ABSTRACT A machine for deforming the end of a piece of metal for handling it for insertion into a forging press or the like to form the finished article. The machine receives, holds and deforms a piece of metal which has been heated to a plastic condition, and has stop means for holding the piece against axial shifting in one direction while its squeezing jaws deform the end of the piece into a holding portion. The swingable jaws of the machine are of a shape 1) that precludes axial shifting of the piece in the other direction and (2) that forms the holding portion into a flattened and axially elongated shape having tool engaging projections.

4 Claims, 16 Drawing Figures l MACHINE FOR FORMING METAL STOCK FOR HOT FORGING REFERENCE TO RELATED CO-PENDING APPLICATION This is a divisional application of my co-pending U.S. application Ser. No. 148,092, tiled May 28, 1972 and entitled Method of Handling Metal Stock for Hot Forging, which issued as U.S. Pat. No. 3,7l3,320 on Jan. 30, 1972.

BACKGROUND oF THE INVENTION In the hot forging'of metal, particularly of metal stock having considerable thickness or diameter, excessive waste of the material has heretofore been necessary in order to provide for handling of the plastic stock while in the forging press. In the prior art, either a piece of excessive length was necessarily used for each article to be finished, or an extra stub was welded onto the end of the piece, in order to provide a holding portion for the gripping tongs used to hold the piece while it was being forged.

Prior art machines for handling such pieces were unsatisfactory because ofthe waste of material which was necessary in order to provide the gripping portion for the tongs, or, in the case where an extra stub was welded to the stock to be deformed, the welded stub would sometimes break off while the piece was being handled.

Because the metal to be forged is often very expensive, it is desirable to utilize only a length of material which is absolutely necessary to provide sufficient metal for the finished article.

SUMMARY OF THE INVENTION The invention relates to the machine for deforming the end of the plastic piece into a tong-holding portion. This machine has an adjustable V-shaped table for accurately positioning the plastic piece relative to the squeezing jaws of the machine. Stop means are provided for the piece for preventing it from shifting axially in one direction while the squeezing jaws are performing their operation. The jaws are swin'gable by fluid power operated means from an open position for receiving the end of the piece and a closing position in which they have squeezed the end of the piece into the particular shaped jaws, thereby forming the end of the piece into a generally transversely flattened and axially elongated shape. Furthermore, the jaws are of such shape that they first contact the piece at a location where the excessive length of the piece joins the remainder of the piece thereby preventing the piece from shifting the other direction as the closing jaws causev the material to be squeezed in an axial direction and into the particular shape formed by the jaws.

These and other objects and advantages of the present invention will appear hereinafter as this disclosure progresses, reference being had to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. ll shows a piece of metal to be forged and which has been cut from a bar stock;

FIG. 2 shows the metal being heated in a furnace of any suitable character to place the metal in a plastic condition;

FIG. 3 is a fragmentary view of a machine in which the end of the plastic metal piece is shaped to deform the excessive length thereof into a holding portion;

FIG. 4 is a view of the piece after it has been deformed at one end;

FIG. 5 is an end view of the piece shown in FIG. 4;

FIG. 6 shows the step of applying the complementary shaped tongs to the piece;

FIG. 6a is an end view of the jaws of the tongs shown in FIG. 6;

FIG. 7 shows the step of placing the piece in a forging press;

FIG. 8 shows the piece after it has been forged;

FIG. 9 is a perspective view of the finished piece, for example, a crankshaft;

FIG. l0 is a perspective view of the squeezing machine for forming the holding portion of the piece, a part of this machine also being shown in FIG. 3;

FIG. 11 is a side view of the machine shown in FIG. l0;

FIG. lla is a fragmentary, plan view of the jaws of the machine-as shown in FIG. l1, in the closed position;

FIG. l2 is an enlarged sectional view of the machine shown in FIG. l1, the view being taken along the line 112-12 in FIG. 1l;

FIG. I3 is a front elevational view of the machine shown in FIG. l0, but showing the squeezing jaws in the fully closed, compressing position, certain parts being shown as removed for clarity in the drawings; and

FIG. 14 is a view of the piece as it is removed from the machine of FIG. 13 after the jaws have again been opened, and this piece being the same as that shown in FIGS. 4 and 5.

DESCRIPTION OF A PREFERRED EMBODIMENT The present invention finds particular utility in handling metal pieces for hot forging, which pieces are of substantial size that make them difficult to securely hold and accurately position in a hammer or press and while being manipulated in the press. These metals are often expensive and it is desirable only to use as short a piece as possible which will at the same time provide the necessary metal to form the finished article.

As shown in FIG. l, a piece P is cut from a supply of stock S so that the piece includes a small length l, for example of a length of one-half inch, and which length 1 is in excess of the length of the piece required to form the finished article. This minimum excess length l is too short to be grasped by the necessary holding tool, such as a pair of tongs T, to be referred to later.

This small minimum length of the piece is deformed, as will appear, so that it results in an axially elongated holding portion which is of a shape that provides a good grip for the tool T.

After the stock has been cut into the piece P with a minimum excess length l, it is placed, by any suitable means, in a furnace F, which may, for example, include electric heating elements E that produce sufficient heat to cause the piece to become sufficiently plastic so it may be deformed under pressure by a machine to be referred to. After the piece has been so heated, it is removed from the furnace F and its end, namely the minimum length l of about one-half inch is deformed to provide a good holding portion as follows.

A particular machine M which has been provided to perform a squeezing action to deform the end has been shown in FIG. 3 and in FIGS. 10 to 13 inclusive. The

machine includes wheel means W at the lower side of the machine frame. The piece P is laid on a V-shaped table 2 of the machine M and its one end abuts firmly against a fixed stop 3 in the table. The table 2 of the machine comprises a pair of downwardly converging, corrugated plates 2a and 2b which are fixed by screws 3a (FIGS. 12), to keep the metal piece P centered in the machine.

The other end 1 of the piece P extends between the jaws 4 and 5 of the machine, which are attached to swingable arms 6 and 7, respectively that in turn are pivoted about a center axis 8. The arms 6 and 7 can be swung from the open position, as shown in FIG. l0, to the fully closed position shown in FIG. 13, by their hydraulic cylinder and piston units 12 and 13, respectively. The hydraulic units are of conventional character and each include a piston 14 and a cylinder 15. In this manner, after the piece p is placed on the table 2 against the stop 3, the cylinder units are extended in the known manner to cause arms 6 and 7 to swing upwardly, consequently causing their jaws 4 and 5 to squeeze the excess length end of the plastic piece P, thereby deforming it into a shape such as shown in FIGS. 4 and 5. While the squeezing operation is taking place, piece P is prevented from shifting axially by the stop 3, thereby insuring that the end 1 of the piece is accurately formed in relation to the remainder of the piece.

In respect to the shape of the jaws 4 and 5, it will be noted that they are shaped to have an inner edge 4a and a which close on the piece P prior to the commencement of the deformation of the piece. This generally wedge shape of the jaws, when viewed in plan, insures that the piece does not jump out, that is shift axially in the direction away from the stop 3, when the jaws deform the end. Thus the stop 3 and the shape of the jaws 4 and 5 hold the piece from axially shifting as the jaws close. Closing of the jaws squeezes the end of the piece, causing it to flow in an axial direction into the remaining portion of the jaws.

The inner, opposed surface of the jaws are also formed of a particular shape so as to cause the end of the piece to be generally flattened in a transverse direction, and a projection 2l formed on the end, due to the recesses 22 in the jaws (FIG. lla).

Thus, as shown particularly in FIGS. 4, 5 and 14, the deformed end is flattened in a transverse direction and thereby becomes wider than the orginal shape and the end is also axially elongated and has a pair of projections 21, one on each side, thereby forming a holding portion for the piece P.

After the end has been so formed, the portion 20 of the piece P is grasped by a large pair of tongs T having jaws 25 and 26 with internal recesses 23 that complement the shape of the projections 21. Thereby, the jaws of the tongs can positively and securely grasp the piece P to prevent it from twisting relative to or dropping from the tongs. It will be appreciated that as the piece P is often of considerable weight and is furthermore subjected to considerable pounding and pressure while in the forging press, it is necessary that the piece by under accurate and absolute control of the operator at all times in order to insure the formation of an accurately formed finished part.

As shown in FIG. 7, the piece P is then inserted in the forging prss FP where the upper die for example, descends rapidly and with considerable pressure on the piece P thereby forming it into the desired shape as determined by the shape of the die 30 and the lower, opposed die 31. In forging the piece to the desired shape, it may be necessary for the operator to turn the piece to several different positions for subsequent strokes of the die 30, and while doing so the piece must be under accurate and positive control of the operator.

After the piece is formed, it is removed from the forging press and a certain amount of flash 33 which is usually relatively thin, is cut from the finished article, such as a crankshaft CS (FIG. 9). The holding portion 20 is also removed from the finished crankshaft CS.

RESUME By means of the present invention, a piece of metal is cut from a bar stock with only a minimum excess length which is to be used for holding it.

The piece is then heated to a plastic condition and the end of excess length is formed to provide a desirable shape which can be grasped by a complementary holding tool. The piece which is then firmly grasped by the tool at the elongated and flattened holding portion is then placed in a forging device such as a press, drop hammer, or the like, for being formed as desired. After the piece has been formed, the elongated holding portion can be cut from the finished article. In this manner only a minimum amount of original bar stock is necessary to facilitate accurate and positive handling by the operator during the forging operation.

The machine provided by the present invention can accommodate different size pieces, prevents axial shifting of the piece while its end is being deformed into an axially elongated, transversely flattened holding portion having projecting means thereon. The machine jaws accurately exert a squeezing force only on the excess length on the end of the piece and into the desired shape.

I claim:

1. A plastic metal deforming machine for deforming the end of a piece of plastic metal while securely holding said piece against axial displacement, said machine comprising; a table for receiving said piece with one end of said piece extending from said table, stop means against which said piece is abuttable to prevent axial displacement of said piece in one direction while said one end is being deformed, a pair of deforming jaws swingable over said one end of said piece for squeezing engagement thereof whereby said end of said plastic piece is flattened transversely and is also axially elongated by flowing into said jaws, power means for swinging said jaws between an open piece receiving position and a closed piece squeezing position, said jaws having opposed piece engaging surfaces which together define a generally V-shaped opening when viewed in plan whereby said jaws first grip said piece at a location spaced from the extreme end of said one end of said piece and consequently prevent axial shifting of said piece in the other direction as the jaws continue to squeeze and deforrn said end of said piece.

2. The machine set forth in claim 1 further characterized in that said jaws have recess means whereby said end of said piece flows into said recess and projections are formed on the piece.

3. The machine set forth in claim 1 further characterized in that said table is of generally V-shape and corngrises a pair'of oppositely inclined table portions. U.S.

erial No. 286,866.

4. The machine set forth in claim 2 further characterized in that said table is of generally V-shape and comprises a pair of oppositely inclined table portions. 

1. A plastic metal deforming machine for deforming the end of a piece of plastic metal while securely holding said piece against axial displacement, said machine comprising; a table for receiving said piece with one end of said piece extending from said table, stop means against which said piece is abuttable to prevent axial displacement of said piece in one direction while said one end is being deformed, a pair of deforming jaws swingable over said one end of said piece for squeezing engagement thereof whereby said end of said plastic piece is flattened transversely and is also axially elongated by flowing into said jaws, power means for swinging said jaws between an open piece receiving position and a closed piece squeezing position, said jaws having opposed piece engaging surfaces which together define a generally V-shaped opening when viewed in plan whereby said jaws first grip said piece at a location spaced from the extreme end of said one end of said piece and consequently prevent axial shifting of said piece in the other direction as the jaws continue to squeeze and deform said end of said piece.
 2. The machine set forth in claim 1 further characterized in that said jaws have recess means whereby said end of said piece flows into said recess and projections are formed on the piece.
 3. The machine set forth in claim 1 further characterized in that said table is of generally V-shape and comprises a pair of oppositely inclined table portions. U.S. Serial No. 286,866
 4. The machine set forth in claim 2 further characterized in that said table is of generally V-shape and comprises a pair of oppositely inclined table portions. 